Database Reference
In-Depth Information
9.3 PROPERTIES
OWL uses the standard RDF properties, with accompanying domain and range
restrictions, and as with RDF, subproperty relationships are also possible. These can
be represented in the Rabbit and Manchester Syntaxes as in the following examples:
“sells” is a Relationship that takes a
concept as an object.
The relation “sells can only have Pub as a
subject.
The relation “sells” can only have Beer
as an object.
ObjectProperty: sells
Domain: Pub
Range: Beer
And a datatype property can be denoted as
“has nick name” is a Relationship that
takes a value as an object.
The relation “has nick name” can only have
a String as a Value.
DataProperty: hasNickName
Domain: Place
Range: xsd:string
Note that the convention for naming properties in Manchester Syntax (and syn-
taxes other than Rabbit, which uses lowercase throughout) is to use camel case, that
is, the first word is lowercase and the first letter of subsequent words is capitalized.
While domain and range restrictions on properties are inherited by their subproper-
ties, this is not the case for other property characteristics like symmetry or transitivity,
which we discuss in a separate section. Most property constraints are global, that is,
they apply for every class that uses that property. In contrast, a “local” property con-
straint will only apply to the property's use with a particular class. Unless otherwise
indicated, the property constraints we discuss are all globally applicable.
9.3.7 e
quivaLent
P
rOPerty
owl:equivalentProperty
states that two properties have the same property
values for a given individual. It is important to note that this is not the same as stating
that the properties mean the same thing. (As an aside, to do that you would have to
use the
owl:sameAs
construct, which would mean treating the classes as individu-
als themselves, which is only allowed in OWL Full or OWL 2.0. For more details,
see Appendix A.)
9.3.8 i
nverse
O
f
The
owl:inverseOf
construct applies to two properties that link the same classes
while reversing the subject and object. For example,
The relationship “owns” is the complement
of “owned by”.
Merea owns MereaMaps.
ObjectProperty: owns
InverseOf: owned_by
Individual: Merea
6
Facts: owns MereaMaps
